1. Field of the Invention
This invention relates to novel binary switches which can cause data streams to cross one another or bypass one another, and to storage/data manipulation systems utilizing these switches to link shift registers.
2. Description of the Prior Art (see end of specification, also)
Various magnetic bubble domain systems are known in the art which combine data manipulation operations and storage on the same magnetic chip. Examples of such systems are shown in U.S. Pat. No. 3,701,125 which illustrates a magnetic bubble domain chip including memory and decoder functions, and U.S. Pat. No. 3,689,902, which describes a bubble domain decoder and storage system having means for clearing information from any or all storage cells.
In addition to the examples listed above, several patents show data rearrangement schemes implemented in magnetic bubble domain technology. In particular, dynamically ordered storage registers are shown which operate on a "most recently used algorithm". In such an apparatus, data is arranged where ease of access is in accordance with its last use. That is, data is stored in the shift register in order of last use so that the last bit of information which has been accessed is in the first, or the access, position of the register. Therefore, it can be read out of the storage without shifting. The next to the last bit of information accessed is stored in the adjacent position so that it can be accessed by shifting the contents of the register only one position. If data is stored in this manner, any desired data item can be reached with considerably less shifting operations on the average than would be necessary if the data had been stored randomly in the shift register. An example of such dynamically reordered storage apparatus implemented in magnetic bubble domain technology is shown in U.S. Pat. No. 3,670,313. Additionally, U.S. Pat. No. 3,797,002 describes a dynamically double ordered shift register memory utilizing a plurality of bidirectional shift registers. Access to data for rearrangement can occur at either end of the shift registers.
Still another dynamically ordered shift register is described in U.S. Pat. No. 3,766,534. In this patent, multi-dimensional dynamic ordering is achieved and multiple bits can be sorted in memory using multiple access positions. This reduces the average access time to data items and also substantially reduces worst case access time for all data items. Still other examples of bubble domain data rearrangement systems are shown in U.S. Pat. Nos. 3,737,881 and 3,701,132.
In the data rearrangement devices described in the listed patents, the magnetic drive field used for moving bubble domains has to be either stopped or reversed in order to provide the bubble domain rearrangement operations. This is a distinct disadvantage since more complicated control circuits are required and more power is used for controlling the magnetic drive field. Additionally, the execution of the various other bubble manipulation functions becomes more difficult since the operation of all bubble devices in the same module is synchronized.
In the present invention, a steady, rotating magnetic drive field is provided in the plane of the magnetic film which supports the bubble domains. All operations are performed without the requirement of stopping or reversing this in-plane drive field. This drive field can be provided by using two sinusoidal magnetic fields which are 90.degree. out of phase with each other, or by using pulse fields (.+-.x, .+-.y), as is well known in the art. If charge coupled device technology is used, the same repetitive sequence of drive pulses is continually used, there being no need to change the drive pulse sequence in any way, or to stop it. Additionally, no gap is created in the data stream as a result of the operations which are performed. The present structure has considerable flexibility and can be applied to all types of data manipulation/storage arrangements.
In addition to the advantage mentioned with respect to the use of a steady, rotating magnetic drive field, the present invention seeks to use intersecting data streams to perform storage/data manipulation operations such as sorting, dynamically ordered storage, etc. All of the patents mentioned previously do not utilize intersecting data streams in which each data stream continually moves during each full cycle of the drive field (or drive pulses) to perform their various operations. However, bubble domain systems for performance of text editing functions using a constant, rotating magnetic drive field are described in copending applications Ser. No. 469,927 now U.S. Pat. No. 3,967,263 and Ser. No. 469,926 now U.S. Pat. No. 3,950,732, filed May 14, 1974. However, the text editing systems described therein do not utilize structure wherein data streams intersect one another or bypass one another continually during the drive field cycle. In the present apparatus, the use of a binary switch instead of freeze/bypass of data bits, results in reordering of data by blocks rather than by bits, as is done in the prior art.
Accordingly, it is a primary object of the present invention to provide novel switch arrangements which can cause data streams to either cross or bypass each other depending upon control signals.
It is another object of the present invention to utilize such novel switches to provide structure that is capable of many data storage/manipulation functions.
It is another object of the present invention to provide a bubble domain apparatus which can alternate between several data structures.
It is a further object of the present invention to provide apparatus for manipulating data streams without altering the original bit pattern after the operations are performed. Thus, it is an object to provide data manipulation in which there will be no loss of original data, no addition of spurious data, and no unwanted internal permutation of the original bit pattern.
It is a still further object of the present invention to provide a bubble domain storage/data handling apparatus which has significant flexibility for application in any type of data/storage management system.
It is another object of the present invention to provide an improved data storage/manipulation structure which can be implemented in several technologies.
It is still another object of the present invention to provide a shift register storage system using binary flow-steering switches for provision of flexible and versatile systems which can be used in any type of data handling apparatus.
It is another object of the present invention to provide a magnetic bubble domain storage/data manipulation apparatus which can provide several data handling operations using a constant repetitive pattern of drive pulses, where the pattern does not have to be altered or stopped in any manner in order to achieve any or all of these data operations.